• Korean journal of applied entomology
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• v.60 no.4
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• pp.339-355
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• 2021

Aphids can damage plants directly by absorbing their phloem sap and indirectly by transferring plant viruses and causing sooty mold. We compared the thermal effect on the development, survivorship, and reproduction of four cereal crop-damaging aphid species, Rhopalosiphum padi, Aulacorthum solani, Aphis craccivora, and Acyrthosiphon pisum using a life table analysis method. We investigated the stage-specific development period, survivorship, adult longevity, and fecundity of the above mentioned four aphids at 10, 15, 20, 25, and 30℃, respectively, and analyzed their life table parameters using the age-stage, two-sex life table analysis. A. solani nymphs could not complete their development to adulthood at 30℃. The intrinsic increase rate of R. padi was the highest at all tested temperatures except for that at 15℃ (0.12, 0.34, 0.47, and 0.32 at 10, 20, 25, and 30℃, respectively), and that of A. pisum displayed negative values at 30℃ (-0.04). It is speculated that R. padi would be a dominant species under high temperature conditions and A. solani is a highly adaptive species at low temperatures through the comparative analysis of the life table parameters of four aphid species damaging to cereal crops.

• Research in Plant Disease
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• v.21 no.3
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• pp.227-230
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• 2015

The ascomycete fungus Fusarium fujikuroi causes bakanae disease in rice and this disease has been reemerging in Korea. Other fungal species including F. graminearum and Magnaporthe oryzae are often associated with F. fujikuroi, hampering pure isolation of F. fujikuroi from rice. In this study, we modified a selective medium for F. fujikuroi as supplementing both pentachloronitrobenzene and hydrogen peroxide into minimal medium. This medium efficiently suppressed the vegetative growth of F. graminearum and M. oryzae, but did not significantly reduce F. fujikuroi growth, providing an efficient tool for isolating F. fujikuroi.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.131-137
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• 2006

This experiment was conducted to select prominent microorganisms with a good insecticidal activity among the ten species, which isolated from soil at the near of Chung-buk, Chung-nam, and Gang-won provinces and made protein crystal endotoxin. As a result, GB-413 strain was finally selected, which showed the high insecticidal activity against susceptible diamondback moth (Plutella xylostella), beet army worm (Spodoptera exigua) and tobacco cutworm (Spodoptera litura) as well as resistant diamondback moth strains. By modifying the cultivation process f.g. lowing the glucose concentration at early cultivation stage and adding the carbon after inducing the spores, the percentage of making spore as well as the number of active spore were increased and the time for cultivation and spore forming was reduced without a reduction of insecticidal activity. These results were not only applied successfully for the optimized cultivation process for a fermentation tank containing five tons capacity, but also improved the possibility of mass cultivation for commercial production.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.353-360
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• 2015

A survey of weed occurrence was conducted to identify problematic weed species in a horticultural crop field to get basic information for effective weed control. Surveys of weed species occurring in horticultural crop fields (garlic, onion, red pepper and Chinese cabbage) were conducted in Chungnam province of Korea from April to October in 2014. A total of 516 sites of the 17 regions were identified as having 114 weed species belonging to 32 families. The most dominant weed species in the horticultural crop fields were Chenopodium album var. centrorubrum (8.83%), followed by Digitaria ciliaris (5.71%), Conyza canadensis (5.46%) and Capsella bursa-pastoris (4.67%). Specifically, as a result of this study, the occurrence of 35 species of exotic weeds, such as Chenopodium album and Taraxacum officinale, were confirmed. Almost 68% of the investigation sites was determined under dominance value 1 (range of cover < 10; numerous individuals) by Braun-Branquet cover-abundance scale, indicating a proper weed control in horticultural crop field. As a result of scientific and technological advances, an improved cultivation method is changing the weed occurrence in agricultural land. Additional research needs to be undertaken for the development of weed control methods through such periodic monitoring of occurrence of weeds.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.09a
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• pp.34-58
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• 2001

Within the paper, an overview of organic farming in Europe countries is given and the Principle and skills of organic agriculture is shortly reported with special regard to Germany. The overview information on European organic farming is covered such as (1)development of organic farming, (2) organic farming organizations, (3)standards and certification, (4)implementation of EU council regulation, (5)state support, (6)implementation of Agenda 2000, (7)training and education, (8)advisory service and research situation. In the paper the principle and skills for organic farming which are practiced actually in the German organic farms is also reported. How to maintain and increase the fertility and microbiological activity of the soil by (1)cultivation of legumes, green manures or deep-rooting crops in multi-annual rotation system, (2)incorporation in the soil organic material, by-products from livestock farming is one of the major principle to organic crop production. Pest and diseases and weeds are controlled by any one, or a combination of the following measure; (1) choice of appropriate species and varieties, (2)appropriate rotation programs, (3)mechanical cultivation, (4)protection of natural enemies of pests through provision of favourable habitat and ecological buffer zone, (5)diversified ecosystems, (6)flame weeding, (7)natural enemies, (8)bio-dynamic preparations, (9)mulching and mowing, (10)grazing of animals, (11)mechanical controls, (12)steam sterilization.

• Korean Journal of Organic Agriculture
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• v.9 no.4
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• pp.71-93
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• 2001

Within the paper, an overview of organic farming in Europe countries is given and the Principle and skills of organic agriculture is shortly reported with special regard to Germany. The overview information on European organic forming is covered such as \circled1 development of organic farming, \circled2organic farming organizations, \circled3standards and certification, \circled4implementation of EU council regulation, \circled5state support, \circled6implementation of Agenda 2000, \circled7training and education, \circled8advisory service and research situation. In the paper the principle and skills for organic farming which are practiced actually in the German organic farms is also reported. How to maintain and increase the fertility and microbiological activity of the soil by \circled1cultivation of legumes, green manures or deep-rooting crops in multi-annual rotation system, \circled2incorporation in the soil organic material, by-products from livestock farming is one of the major principle to organic crop production. Pest and diseases and weeds are controlled by any one, or a combination of the following measure ; \circled1choice of appropriate species and varieties, \circled2appropriate rotation programs, \circled3mechanical cultivation, \circled4protection of natural enemies of pests through provision of favourable habitat and ecological buffer zone, \circled5diversified ecosystems, \circled6flame weeding, \circled7natural enemies, \circled8bio-dynamic preparations, \circled9mulching and mowing, \circled10grazing of animals, ⑪mechanical controls, ⑫steam sterilization.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.4
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• pp.110-119
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• 2004

This research was conducted to develop spraying cultivation method using forest topsoils in order to restore the disturbed slopes. In November the researcher collected a depth of 5 cm of topsoils from a well developed forest, after the fallen leaves were cleared. The essential results of the research are as follows: In the case of using the forest topsoils, during the early stages of planting, time is necessary for the desired vegetation to reach a similar state to the vegetation being restored. The best possible effect is obtained through a method utilizing forest topsoil(30%)+loam silt soil(70%)+seeding with grasses and native plants including trees, shrubs, and herbs. Several plants such as Pinus densiftora, Potentilla fragarioides, Miscanthus sinensis, Erigeron canadensis seemed to be naturally emerged from the topsoils From this experiment, it was recommended that environment potential within topsoil should be comprehended. Also, topsoil deposit and gathering methods should be experimented properly.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.103-103
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• 2019

Glycyrrhizae radix, commonly known as licorice, is a perennial herb belonging to Leguminosae and also includes various components such as, glycyrrhizin, liquiritin, liquiritigenin and isoliquiritigenin etc. Licorice has been widely used in East Asia as a medicine having pharmacological effects like antioxidants, anti-bacterial, anti-inflammatory, anti-cancer and immune modulatory activities. Among various licorice, Glycyrrhiza (G.) uralensis G. glabra and G. inflata are used for pharmaceutical purposes in Korea. However, cultivation of licorice has some problems such as low quality, low productivity, and early leaf drop. Korea Rural Development Administration developed new cultivars Wongam and Sinwongam, which are improved in cultivation and quality. To register the newly developed cultivar (s) on Ministry of Food and Drug Safety in Korea as a medicine, it is necessary to prove the similarity and difference through the comparative studies between already-registered species and new cultivars. Some fungi and bacteria usually in the human oral cavity and intestines exist as harmless state in human body. Also, the skin and genital infections by fungi can lead to toxic systemic infections and are accompanied by flushing, rashes, burning or painful sensation. The influences of licorice varieties on fungi and bacteria might be an evidence to prove the outstanding effect of newly developed licorice variety. In this study, the antifungal and antibacterial activity was investigated using newly developed licorice varieties Wongam, and Sinwongam against various fungi and bacteria. These results means newly developed licorice could be used as a replacement of already-registered species in terms of antifungal and antibacterial application.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.10-22
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• 2022

This study investigated field data to understand the spatio-temporal distribution of pollinating insects and buckwheat flowers. We set the in-situ observation sites in different locations to get altitude and cropping system distribution data for five years (2016 to 2020) in Korea. Twenty-five different insect species, belonging to 8 orders, were recorded. Over the past five years, species from the orders Diptera and Hymenoptera were the principal visitors. Hymenoptera was mainly represented by honey bees (Apis cerana), while Diptera was represented by bean seed fly (Delia platura) and several other species. Some bees and other Hymenoptera species could, however, act as co-pollinators because of their high relative frequency and activity. Compared with open-field cultivation (conventional), the pollination mediating effect of flies and bees was superior in net house, so the yield was high, and it was also found to be slightly higher in the mixed treatment of flies and bees than in the single treatment. Based on the above results, flies and bees were found to be the most active pollinating insects in buckwheat and it is necessary to actively utilize the selected insects to improve buckwheat productivity. This relationship will be utilized in establishing the system of seed production on pollinating regulation of a primary plant.

• Journal of Ecology and Environment
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• v.46 no.2
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• pp.111-125
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• 2022

Background: Zanthoxylum armatum is one of the 30 prioritized medicinal plants for economic development of Nepal with a high trade value. Understanding the ecology of individual species is important for conservation and cultivation purposes. However, relation of ecological factors on the distribution and populations of Z. armatum in Nepal remain unknown. To address this knowledge gap, an attempt has been made to study the population structure, distribution, and regeneration potentiality of Z. armatum. Vegetation sampling was conducted at six different localities of Salyan district along the elevation range of 1,000 m to 2,000 m. Results: Altogether 50 plant species belonging to 44 genera under 34 families were found to be associated with Z. armatum. Significantly higher species richness was found at Rim (1,400-1,700 m) and Chhatreshwori (1,800-2,000 m) and lower at Kupinde (1,600-1,800 m). The highest population density of Z. armatum was at Kupinde (1,600-1,800 m) with a total of 1,100 individuals/ha. and the lowest at Chhatreshwori (1,800-2,000 m) with 740 individuals/ha. Based on the A/F value (Whitford index), it can be said that Z. armatum has random distribution in the study area. The plants were categorized into seedlings, saplings and adults based on plant height and the status of natural regeneration category determined. The regeneration potentiality of Z. armatum in the study area was fair with the average seedlings and saplings densities of 150 and 100 individuals/ha. Respectively. A Shannon-Weinner index mean value of 2.8 was obtained suggesting high species diversity in the study area. Conclusions: The natural distribution and regeneration of Z. armatum is being affected in the recent years due to anthropogenic disturbances. Increasing market demand and unsustainable harvesting procedures are posing serious threat to Z. armatum. Thus, effective conservation and management initiatives are most important for conserving the natural population of Z. armatum in the study area.